Currently, with continuous development of the display technology, the 3D display technology has attracted a great deal of attention. The 3D display technology enables images to be stereoscopic and look like real. A basic principle for the 3D display lies in that different images are respectively received by a left eye and a right eye of a person and then are overlapped to reproduce image information by the human brain to form stereoscopic images.
However, in the current 3D display technology, an observer can only see a single 3D image, and 3D images in different view angles cannot be observed. As shown in FIG. 1, a display device is indicated as N. Take a hexahedron M in a 3D scene as an example. Generally, when standing at an observation position A, an observer can only see one 3D image of the hexahedron M. In this 3D image only a surface a, a surface b and a surface c can be observed, and other surfaces of the hexahedron M cannot be seen. When the observer moves to an observation position B, the observer still sees the previous 3D image, and the observer cannot experience a real-life visual effect that different 3D images can be seen from different view angles, and thus, a viewing experience of the observer is decreased.